Graham Rahal topped the times in the final practice session ahead of today's Verizon IndyCar Series season finale at Sonoma.

Rahal, who bolted on a set of soft-compound Firestones, ended the morning with a 1m16.9608s, 0.7s clear of the similarly red-shod Spencer Pigot. Title contender Scott Dixon was third-fastest ­– ­and quickest on the blacks – at 1m17.6849s, 0.02s slower than Pigot, leaving Helio Castroneves and polesitter Josef Newgarden rounded out the top five.

After a surprising frantic start marked by cars contesting corners on the way down the hill and then running side-by-side down the back straight – all on the first lap of green – the field managed to settle itself down and complete an almost incident-free morning, interrupted only by a brief red flag to rescue Max Chilton following a spin at Turn 3.

Prior to the late experimentation with reds (which had also involved Carlos Munoz and Conor Daly, who finish ninth and 11th-fastest respectively), there were some familiar names leading the times. Castroneves set the early benchmark at 1m18.6112s before his time was lowered by championship long-shot Alexander Rossi, who in turn was bettered by Dixon. Rossi ultimately finished the morning sixth-fastest.

Elsewhere, it was a low-key morning for half of the Penske fleet, with Simon Pagenaud finishing the session in P16, three places ahead of Will Power. Charlie Kimball, meanwhile, spent virtually the whole session in the pits before scrambling out with just enough time to complete two laps.

The Verizon IndyCar Series will return to the track for the 85-lap race at 3:30pm PT.